The GIF project: Tracing the evolution of galaxy formation

The GIF project is a joint effort of astrophysicists from the MPA and from Israel. Its goal is to investigate the properties of galaxies in the context of hierarchical structure formation.
Some of the people involved in the project are: The GIF project has carried out a set of high-resolution N-body simulations of four popular CDM universes in cosmologically representative volumes (the code was kindly provided by the VIRGO Supercomputing Consortium. VIRGO has also used the simulations for some of their studies). Afterwards, galaxies were added using semi-analytical recipes on halo merger trees derived directly from the simulations themselves. This has been the first (and to-date still is) the only work which combines the most powerful state-of-the-art computer simulations with semi-analytical models in this way.
Shown below is one of the clusters from the tauCDM simulation at z=0. The size of the region shown is 21x21x8 Mpc/h.

Shown is the density of the Dark Matter distribution using a log colour scale.
Click here for a high quality mpeg movie which shows the evolution of this cluster from a redshift of 20 to present time (Dark Matter only).
The same comoving region looks like this if galaxies are added:

The dark matter is shown in grey scale. Galaxies are shown as circles colour-coded according to their star formation rate: the sequence red, yellow, green and blue represents an increasing rate of star formation. At early times (top left panel) there exist only a few galaxies forming stars at a very high rate. As time goes on, from z=3 to z=0, more galaxies form and, at the same time, some galaxies run out of gas, form fewer stars and become green, yellow and red. At the present time (z=0), red galaxies populate the central region of the cluster, whereas blue galaxies can be found in the outskirts of the system. This is very similar to what is observed in the real Universe.
A slice of thickness 8 Mpc/h through the whole simulation box (which is 85 Mpc/h on a side) would look like this. The colours now denote the B-V colours of the galaxies, ranging from red for ellipticals to blue for irregulars.


The consortium is now using these techniques to add the galaxy population to high resolution simulations constrained to reproduce the observed large-scale structure of the local Universe. See HERE for an image of the dark matter distribution in one of these constrained realisations.
Here is a list of publications from GIF:
If you have any comments, if you are interested in GIF, or if you want to use some of the pictures shown here please send a mail to Antonaldo Diaferio or to Guinevere Kauffmann.
Last modified: Fri Jan 14 11:46:05 MET 2000 by Virgo Administrator